Am 12.04.2011 04:58, schrieb rantingrick: > That's sounds good MRAB! After you mentioned this i had an epiphany... > why not just add an extra argument to dict.update? >>>>> dict.update(D, clobberexistingkeys=False) This is AFAICS inconsistent to the possibility to do dict.update(a, k1=v1, k2=v2). Then you cannot set the key clobberexistingvalues to False via the update method any longer... Thomas